Detection of ovalbumin in egg white, whole egg and incurred pasta using LC–ESI-MS/MS and ELISA

• Published in: Food research international Vol. 52; no. 2; pp. 526 - 534
• Main Authors: Azarnia, Sorayya, Boye, Joyce I., Mongeon, Vanessa, Sabik, Hassan
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Kidlington Elsevier Ltd 01-07-2013; Elsevier
• Subjects: Biological and medical sciences; Egg allergens; Egg and egg product industries; ELISA; Food industries; Fundamental and applied biological sciences. Psychology; General aspects; Heat processing; Mass spectrometry; Methods of analysis, processing and quality control, regulation, standards; Ovalbumin; Heat processing; Ovalbumin; Egg allergens; Mass spectrometry; ELISA; Egg; Liquid chromatography; Egg white; Enzyme immunoassay; Heat; Analysis method; Egg product; Control method; Detection; ELISA assay; Allergen
• ISSN: 0963-9969; 1873-7145
• DOI: 10.1016/j.foodres.2013.02.039

Ovalbumin is one of the principal proteins responsible for IgE-mediated egg allergy. In this study, the effect of thermal processing on the antigenicity of ovalbumin in control ovalbumin, egg white and whole egg powders and incurred pasta preparations were evaluated. Solutions (4% w/v) of control ovalbumin, egg white and whole egg were separately boiled for 0, 5, 10, 15min and then freeze-dried. Accurately weighed portions of semolina used in the pasta were separately incurred with the egg white and whole egg powders, to give concentrations of 10, 100 and 1000ppm. Dried pastas were boiled for 15min. After tryptic digestion, samples were analyzed for the presence of ovalbumin using liquid chromatography–electrospray ionization-mass spectrometry (LC–ESI-MS). Enzyme linked immunosorbent assay (ELISA) kits were also used to detect the presence of egg in the raw and cooked pastas. MS coverage of ovalbumin peptides was higher in non-heated samples compared to heated samples (P<0.05). The lowest peptide coverage was observed in the pasta samples. The allergenic epitope peptide fragment ISQAVHAAHAEINEAGR was detected in all egg white incurred samples, whereas it was not detected in the whole egg incurred samples heated for either 10min or 15min. EDTQAMPFRV allergenic epitope was present in all samples containing egg white and whole egg. Of all the ovalbumin epitopes detected by MS, only the allergenic epitope EDTQAMPFRV was detected in the raw pasta samples. Four other non-epitope peptide fragments identified which could be used for the detection of egg were GGLEPINFQTAADQAR, LTEWTSSNVMEER, VTEQESKPVQMMYQIGLFR and EVVGSAEAGVDAASVSEEFR. Both LC–MS and ELISA results were negative for all incurred cooked pasta samples. The results clearly show that egg allergen detection in pasta is affected by matrix and processing.
•ESI-MS and ELISA were used to determine the presence of ovalbumin in pasta.•Five peptide fragments were identified by MS which could be used for egg detection.•The persistent allergenic epitope identified after heating was EDTQAMPFR(V).•Heating decreased egg allergen recovery.•No egg proteins were detected in cooked incurred pasta using both ELISA and MS.